Pregnant women, particularly those from underserved populations, often have a multitude of behavioral risks that threaten positive pregnancy and birth outcomes, as well as the future health of mother and baby. This application represents innovative research for impacting the promotion of healthy behaviors among pregnant women. The objective is to develop and test the first computer tailored intervention for pregnant women to address multiple behavioral risks. Healthy Pregnancy: Step by Step offers tailored guidance on the adoption and maintenance of smoking cessation, stress management, and fruit and vegetable consumption. This application offers innovation through the use of varying levels of tailoring across behaviors and a co-variation design through which multiple behaviors can be treated effectively and efficiently. The successful completion of Phase I demonstrates that a stage-matched computer tailored intervention is acceptable to pregnant women, feasible to disseminate in health clinics in conjunction with prenatal care, and has initial efficacy with multiple behaviors. The primary goals of Phase II are to complete and enhance the development of the intervention and to assess the efficacy in a randomized clinical trial involving 368 pregnant women from two non-profit health centers that treat underserved populations. In addition, supplemental intervention components will be created including printed feedback reports, a multiple behavior stage-based manual, and Spanish versions of all intervention materials. This intervention offers a cost-effective, science- based, and easily deliverable solution to improve multiple health behaviors, and overall health and well-being, of populations of pregnant women. Support from several distribution channels bolsters the commercial potential for this program and the promise for widespread dissemination. PUBLIC HEALTH RELEVANCE: Promoting healthy behaviors during pregnancy and postpartum is of great public health importance. This research proposes to develop and test a population-based, multiple health behavior change program for pregnant women that offers guidance on the adoption and maintenance of smoking cessation, stress management, and fruit and vegetable consumption. This computer tailored intervention offers a cost- effective, science-based, and easily deliverable solution to improve multiple health behaviors, and overall health and well-being, of populations of pregnant women.